The present invention relates to a transmission device for a phase shifter and an actuator device for a phase shifter. The transmission device includes a support, a lead screw nut mechanism and an automatic locking device. The automatic locking device includes a shaft connector rotatably supported on the support and configured to be in transmission connection with a driven connector of a driving device; a locking connector which is in transmission connection with the shaft connector, is in transmission connection with the lead screw, has a locking element and is movable relative to the shaft connector and the lead screw; and a locking spring. When the driven connector is decoupled to the shaft connector, the locking spring biases the locking connector in a first position, in which the locking element engages a counter-locking element on the support. When the driven connector is decoupled to the shaft connector, the locking connector is moved by the driven connector to a second position, in which the locking element disengages the counter-locking element on the support. Calibration of the phase shifter may be saved when the driving device is replaced or repaired.